<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>网页输出</title>
</head>
<body>
<script>
    // alert("输出1");
    document.write("输出2");
    console.log("输出3");
    张三 = "张三";
    alert(张三);
</script>
</body>
</html>